A dual-color visual hydrazine fluorescence probe, its preparation method and application

Abstract

The present application discloses a dual-color visualized hydrazine fluorescent probe and its preparation method and application, belonging to the field of detection technology. The present application uses ESIPT-type imide-based molecules coupled with benzoic anhydride and their derivatives as dual-color visualized hydrazine fluorescent probes, realizes efficient and rapid detection of hydrazine in three states of solid, liquid and gas through dual-color visualized changes, and uses the dual-color visualized hydrazine fluorescent probe to realize accurate detection of the hydrazine content in actual samples.

Description

Technical Field

[0001] The present application relates to a dual-color visual hydrazine fluorescent probe, a preparation method thereof, and an application thereof, belonging to the technical field of detection. Background Art

[0002] Hydrazine (N 2 H 4 ) is a colorless, strongly reducing, corrosive and highly toxic compound with a strong ammonia smell and is soluble in water. As a high-energy fuel, hydrazine is used in the propulsion systems of rockets and satellites, and is also widely used as a chemical raw material in the chemical manufacturing of foaming agents, insecticides, antioxidants, polymers, etc., and is also used in water treatment. Although the application fields of hydrazine are very extensive, hydrazine is a known carcinogen, posing health risks and environmental protection hazards. It is extremely important to timely detect the concentration of hydrazine in workplaces, industrial processes and the environment to help prevent accidents. Currently, there are various detection methods for hydrazine. Common traditional technical means such as spectrometry, chromatography, mass spectrometry, etc. often have the problem that the sample pretreatment in the hydrazine detection process is usually rather cumbersome. For example, the sample matrix is complex and contains various interfering substances, affecting the accuracy of detection; hydrazine is volatile and chemically unstable, and special protection measures need to be taken during the pretreatment process to prevent the volatilization or degradation of hydrazine; traditional detection means usually rely on large-scale instrument equipment such as mass spectrometers and chromatographs, and the operation is cumbersome and time-consuming.

[0003] Compared with traditional detection means, the fluorescence probe method for detecting hydrazine hydrate has the advantages of simple operation, small error and higher sensitivity, and can also achieve fluorescence imaging for the refined detection of hydrazine in vivo. Currently, the fluorescence probes for detecting hydrazine hydrate can be generally divided into two categories: one is the fluorescence probe with fluorescence from non-existent to existent ( Tetrahedron 2024, 161 , 134006.); the other is the fluorescence probe with fluorescence changing from one emission to another ( Chem. Eng. J. 2021, 415 , 128975.). However, these examples only have a change in one wavelength and cannot better and precisely detect hydrazine under external interference. More importantly, currently, the imide-based probes have not achieved the detection of hydrazine in solid, liquid and gas states. Therefore, a rapid, efficient and hydrazine detection means with multiple wavelength changes is needed. Summary of the Invention

[0004] In order to solve the problem in the prior art of detecting hydrazine by fluorescence method that it is difficult to achieve rapid and efficient detection of hydrazine in the three states of solid, liquid and gas at the same time, the present application provides a preparation and detection method of a dual-color visual hydrazine fluorescence probe. By using the fluorescence method, when the probe reacts with hydrazine, obvious fluorescence changes will occur, and the range of fluorescence changes from colorless to yellow and then to blue-green during the detection is used to realize the dual-wavelength visual fluorescence detection of the content of hydrazine, so as to realize the efficient detection of hydrazine in solid phase, gas phase and liquid phase systems that is relatively universal and convenient without relying on instrument equipment.

[0005] The present application adopts the following technical solutions:

[0006] According to one aspect of the present application, a dual-color visual hydrazine fluorescence probe is provided, and the dual-color visual hydrazine fluorescence probe has the structure shown in Formula I:

[0007] Formula I;

[0008] Wherein, R 1 is selected from one of N(CH 3 ) 2 , OMe, CH 3 , H, Br, CF 3 , NO 2 .

[0009] In the present application, the dual-color visual hydrazine fluorescence probe includes an imide-based molecule or its derivative coupled by an ESIPT class and benzoic anhydride.

[0010] According to another aspect of the present application, a preparation method of a dual-color visual hydrazine fluorescence probe is provided, including the following steps:

[0011] React a mixture containing benzoic anhydride, ESIPT-based material, and acetic acid to obtain the visual hydrazine fluorescence probe.

[0012] Optionally, the benzoic anhydride is selected from at least one of the compounds having the structure shown in Formula II:

[0013] Formula II;

[0014] Wherein, R 1 is selected from one of N(CH 3 ) 2 , OMe, CH 3 , H, Br, CF 3 , NO 2 .

[0015] Optionally, the ESIPT-based material is selected from the compound having the structure shown in Formula III:

[0016] Formula III.

[0017] Optionally, the molar ratio of the benzoic anhydride to the ESIPT-based material is 1:1 to 10.

[0018] Optionally, the reaction conditions include: a reaction temperature of 40 to 80 °C and a reaction time of 4 to 72 h.

[0019] Optionally, after the reaction process ends, it further includes the processes of cooling the reaction solution to room temperature, extraction, drying, and separation.

[0020] According to another aspect of the present application, there is also provided an application of the above-mentioned dual-color visual hydrazine fluorescent probe or the dual-color visual hydrazine fluorescent probe obtained according to the above preparation method in hydrazine detection.

[0021] Optionally, the conditions for hydrazine detection include: hydrazine or hydrazine-containing substances being in at least one of the solid, liquid, or gaseous states.

[0022] Optionally, the application includes: contacting the dual-color visual hydrazine fluorescent probe with hydrazine or hydrazine-containing substances for reaction, and accurately detecting the hydrazine content by obtaining the fluorescence color change and fluorescence spectrum information of the hydrazine or hydrazine-containing substances.

[0023] The beneficial effects that can be produced by the present application include:

[0024] The dual-color visual hydrazine fluorescent probe provided by the present application can achieve efficient and rapid detection of hydrazine through dual-color visual changes in the solid, liquid, and gaseous states, and accurately detect the hydrazine content in actual samples by using the dual-color visual hydrazine fluorescent probe. Description of the Drawings

[0025] Figure 1 1H NMR spectrum of Compound 6 in the example of the present application;

[0026] Figure 2 Fluorescence spectra of Compound 6 reacting with 1 equivalent and 10 equivalents of hydrazine hydrate in a mixed solvent of ethanol and water in the test example of the present application, where the concentration of Compound 6 is 25 μM;

[0027] Figure 3 1H NMR changes of substances during the reaction of Compound 6 with hydrazine in the liquid state in the test example of the present application;

[0028] Figure 4 Visual color changes during the reaction of hydrazine with Compound 6 in the vapor state in the test example of the present application;

[0029] Figure 5 During the reaction of Compound 6 with hydrazine in the solid grinding state in the test example of the present application, where Figure 5 a in is the visual color change, Figure 5where b is the fluorescence spectrum;

[0030] Figure 6 This is for visualizing the color change of hydrazine in the actual sample by dual - color visualization detection in the test examples of this application.

[0031] Figure 7 This is a schematic diagram of the reaction process of this type of molecule with hydrazine in the liquid state of Compound 6 in the test examples of this application. Detailed implementation manners

[0032] The present application will be described in detail below in conjunction with the embodiments, but the present application is not limited to these embodiments.

[0033] Unless otherwise specified, the raw materials in the embodiments of the present application are all purchased through commercial channels.

[0034] Unless otherwise specified, the test methods are all conventional methods, and the instrument settings all adopt the settings recommended by the manufacturer.

[0035] The preparation route and product of the dual - color visual hydrazine fluorescence probe in the present application are shown in Formula - 1:

[0036] Formula - 1;

[0037] The imide - type compound coupling ESIPT and benzoic anhydride, that is, the dual - color visual hydrazine fluorescence probe, can be integrally prepared through a one - step condensation coupling reaction. When R1 in Formula - 1 takes different groups, the dual - color visual hydrazine fluorescence probe specifically corresponds to Compounds 3 - 9.

[0038] Taking Compound 6 as an example, the following preparation and test research are carried out:

[0039] Example 1

[0040] Synthesis of the dual - color visual hydrazine fluorescence probe (Compound 6): Weigh 1 equivalent of Compound 1 and 1.2 equivalents of Compound 2 into a round - bottom flask, add 20 mL of acetic acid, and react at 55 o °C for 12 h. After the reaction solution is cooled to room temperature, it is extracted three times with dichloromethane. The combined organic phases are dried with anhydrous sodium sulfate, and the solvent is removed by a rotary evaporator and then separated by column chromatography (SiO 2 ). The eluent is petroleum ether: ethyl acetate = 4:1. The white solid Compound 6 can be obtained with a yield of 85%.

[0041] 1H NMR spectrum of Compound 6: 1 1H NMR (DMSO - d 6): δ = 8.08 - 8.06 (m, 1H), 8.03(s, 8H), 8.00 - 7.94 (m, 4H), 7.57 (s, 2H), 7.41 - 7.37 (m, 3H), 2.52 (s, 3H). Specific spectra are shown in the appendix Figure 1 .

[0042] A series of other imide compounds can be obtained by the above method, and the compounds are characterized by means such as nuclear magnetic resonance and mass spectrometry.

[0043] Test Example 1

[0044] A standard solution of compound 6 in a 1:10 (volume ratio) mixture of ethanol and water at 25 μM was prepared, and its fluorescence spectrum was measured. Then, 1 equivalent and 10 equivalents of hydrazine hydrate were added to it for reaction. After the reaction reached thermodynamic stability, its fluorescence spectrum was measured again as shown in the appendix Figure 2 As shown, when 1 equivalent of hydrazine hydrate was added, a new emission peak appeared at around 570 nm. When 10 equivalents of hydrazine hydrate were added, a new emission peak appeared at around 460 nm. Through the measurement of the excitation spectrum, it was determined that both of them were excited by light at 370 nm to measure the emission spectrum.

[0045] Test Example 2

[0046] Schematic diagram of the reaction process of this type of molecule with hydrazine when compound 6 is in the liquid state is as shown in Figure 7 shown:

[0047] A deuterated DMSO standard solution of compound 6 at 10.0 mM was prepared, and its hydrogen spectrum was measured. Then, 2 equivalents of hydrazine hydrate were added to this standard solution, and kinetic tracking of the reaction time was carried out. The results of the nuclear magnetic resonance hydrogen spectrum measurement are as shown in Figure 3 shown. After 10 minutes, the methyl peak of compound 6 disappeared, and a set of corresponding methyl peaks belonging to compound 11 appeared; after 24 hours, the methyl peak of compound 11 disappeared, and a set of corresponding methyl peaks belonging to compound 12 appeared.

[0048] Test Example 3

[0049] A chloroform standard solution of compound 6 at 10.0 mM was prepared, and a writing brush was placed in this standard solution for 10 minutes. Then, the writing brush was used to write NH 2 NH 2 on the filter paper and then dried with a hair dryer. The prepared sample was placed above hydrazine hydrate, and then the change in fluorescence color with evaporation time was tracked. The change in visible color was recorded by taking pictures with a mobile phone under irradiation with a 365 nm ultraviolet lamp. The results are as shown in Figure 4As shown, when Compound 6 was placed on hydrazine vapor for 1 minute, the pattern turned orange-yellow under 365 nm ultraviolet light. After another ten minutes, the pattern turned white under 365 nm ultraviolet light. After another 30 minutes, the pattern turned blue under 365 nm ultraviolet light.

[0050] Test Example 4

[0051] 3 mg of Compound 6 was placed in a mortar, and then 1 equivalent of hydrazine hydrate was added for grinding. After grinding for 10 minutes, the change in the visualized color was recorded by taking a photo with a mobile phone, and the solid was placed under a solid fluorescence tester to record the change in its fluorescence spectrum. The results are shown in a of the figure. After grinding with hydrazine hydrate for 10 minutes, the solid was orange-yellow under 365 nm ultraviolet light. After adding hydrazine hydrate to Compound 6 and grinding, the fluorescence spectra at different times were measured. The results are as Figure 5 shown in b. After grinding with hydrazine hydrate for 10 minutes, a new emission peak appeared at around 600 nm in its fluorescence spectrum. After grinding with hydrazine hydrate for 1 hour, the emission peak in the fluorescence spectrum showed a blue shift. The solid was blue under 365 nm ultraviolet light, and the fluorescence intensity decreased. On this basis, 9 equivalents of hydrazine hydrate were added for grinding. After grinding for 10 minutes, the change in the visualized color was recorded by taking a photo with a mobile phone under 365 nm ultraviolet light irradiation, and the solid was placed under a solid fluorescence tester to record the change in its fluorescence spectrum. Through the test of the excitation spectrum, it was determined that both were excited by light at 370 nm to test the emission spectrum.

[0052] Test Example 5

[0053] Taking Compound 6 as an example, the efficacy of the visual fluorescence probe 6 in detecting hydrazine in actual samples was further studied. Rice was soaked in hydrazine at different concentrations (1 mM and 10 mM) for 30 minutes, and then the solution was filtered off. The rice was further dried with a hair dryer to obtain hydrazine-contaminated rice. Then the solutions of Compound 6 were sprayed onto the rice contaminated with different concentrations of hydrazine, and the change in the visualized color was recorded by taking a photo with a mobile phone under 365 nm ultraviolet light irradiation. The results are as Figure 6 shown. After spraying the solution of Compound 6 on the hydrazine-contaminated rice, obvious fluorescence signals were shown under 365 nm ultraviolet light, and different visualized colors (from orange-yellow to blue) were shown for rice with different hydrazine contents. In contrast, no changes were observed for the hydrazine-contaminated rice or the solution of Compound 6 under ultraviolet light irradiation. Therefore, the fluorescence probe 6 can effectively detect hydrazine in food samples.

[0054] As described above, these are only several embodiments of the present application and do not impose any form of limitation on the present application. Although the present application is disclosed above with preferred embodiments, it is not intended to limit the present application. Any person skilled in the relevant art can make some changes or modifications within the scope of the technical solution of the present application by using the disclosed technical content, and these are all equivalent to equivalent embodiments and fall within the scope of the technical solution.

Claims

1. Application of a dual-color visualized hydrazine fluorescent probe in the preparation of a hydrazine detection reagent, characterized in that: The dual-color visualized hydrazine fluorescent probe has a structure shown in Formula I: Wherein, R1 is selected from one of N(CH3)2, OMe, CH3, H, Br, CF3, and NO2; The dual-color visualized hydrazine fluorescent probe is an imide-based molecule or a derivative thereof coupled with ESIPT and benzoic anhydride; The dual-color visualization is a dual-color visualization of the hydrazine fluorescent probe, in which the luminescence range changes from colorless to yellow to blue-green during detection.

2. The use according to claim 1, characterized in that: The steps include: A mixture containing benzoic anhydride, ESIPT-type materials and acetic acid is reacted to obtain the visualized hydrazine fluorescent probe.

3. The use according to claim 2, characterized in that: The benzoic anhydride is selected from at least one of the compounds of the structure shown in Formula II: Wherein, R1 is selected from one of N(CH3)2, OMe, CH3, H, Br, CF3, and NO2.

4. The use according to claim 2, characterized in that: ESIPT materials are selected from compounds of the structure shown in formula III:

5. The use according to claim 2, characterized in that: The molar ratio of the benzoic anhydride to the ESIPT material is 1:1-10.

6. The use according to claim 2, characterized in that: The reaction conditions include: reaction temperature of 40 to 80° C., and reaction time of 4 to 72 hours.

7. The use according to claim 2, characterized in that: After the reaction process is completed, the reaction liquid is cooled to room temperature and then extracted, dried and separated.

8. The use according to claim 1, characterized in that: The conditions for hydrazine detection include: hydrazine or a substance containing hydrazine is in at least one of a solid state, a liquid state or a gaseous state.

9. The use according to claim 1, characterized in that: The application includes: contacting and reacting a dual-color visualized hydrazine fluorescent probe with hydrazine or a hydrazine-containing substance, and realizing accurate detection of the hydrazine content by acquiring the fluorescence color change and fluorescence spectrum information of hydrazine or the hydrazine-containing substance.

Images